The Deconstructed Fire Sprinkler System

Have you ever gazed at the ceiling inside a business office, educational facility, or other structure and wondered how the fire sprinkler systems work? Well you’re in luck because we’re going to dissect one of the most effective fire safety systems for quickly reducing heat and often containing a fire until fire fighters can arrive.

Fire sprinkler systems are made up from a network of pipes in the infrastructure of a facility with sprinkler heads placed at strategic intervals. While similar in appearance, fire protection systems like sprinklers are much more complex than your home irrigation system.

The typical head of a sprinkler system (what you see sticking out of the ceilings) is a metal housing which has several functioning parts that work together to activate quickly.

System of piping connected to a water supply source.

Trigger mechanism

Plug

Deflector plate

So, we’ve got the main pieces, but how do they all come together?

Large or small, a fire steadily increases the air temperature directly above it. Smoke and toxic gases rise from the source and spread along the ceiling. This is one reason why you get as low as possible and move quickly to safety if you’re ever find yourself in a situation where there is heavy smoke and increasing heat.

Eventually the air currents in the room that rise, forces the heat and gases down the walls. It’s a very short amount of time that a small fire can grow to the point where a flashover occurs. What this means is that a room gets so hot (usually between 1,000° and 1,500°) that the room spontaneously ignites.

However, with a fire safety system like a sprinkler, as the heat from the fire source moves onto the ceiling, it comes in contact with the trigger mechanism, a glass tube usually filled with a glycerin-based liquid that expands when heated. The combination of liquid expanding inside a solid structure builds pressure and causes the thin glass tube to burst. It is designed to break once it hits a heat threshold of usually 155 degrees.

While intact, the trigger mechanism is assembled in a way that it prevents the plug from moving. However, once the trigger bursts, water pressure from behind the plug is no longer held back and begins to flow freely from the pipes in the ceiling.

If water were to pour straight out of a pipe in the ceiling, it would be a fairly ineffective way to contain a fire that wasn’t directly underneath. To combat this, a deflector plate comes into play and placed under the pipe opening, works to spread water in an even and consistent pattern, maximizing reach around the room.

To prevent water damage in other areas and rooms that may not be affected by the fire, a typical water sprinkler system head is activated by heat one at a time.

Fire safety protection systems are designed to prevent as well as be the first line of defense in a situation where a fire occurs. Whether it’s a residential fire prevention and alert system, a fire protection system for business offices, or a fire life safety system for school campuses, having a properly installed and maintained system will save lives and property. Sprinkler systems will also help to reduce the impact of a fire as well as help first responders in their efforts to extinguish the fire.